Henry Winkler enjoyed a very extended adolescence as Fonzie, who rode around on his motorcycle and always had the best chicks, on seminal ’70s sitcom “Happy Days.”

Fonzie came to symbolize everything that was cool about the ’50s to TV viewers in the ’70s, and his leather jacket was enshrined at the Smithsonian Institution’s National Museum of American History in Washington, D.C. — ironic since the censors at ABC initially refused to allow Fonzie to wear a leather jacket, asserting that such garb would make him appear to be a hoodlum. In the end, Fonzie got his leather jacket, and TV Guide named him the fourth greatest television character of all time.

Winkler told Hoda Kotb and Kathie Lee Gifford on the “Today” show in 2014 that he goes to D.C. to visit the jacket; indeed, he visited in 2008, but the jacket has not been on display for the past several years — drawing a few online complaints — replaced by Farrah Fawcett’s swimsuit.

But curators have assured Variety that while the jacket may not be currently on view, it is very much part of the museum’s permanent collection: “As it is made from leather, organic materials, we are not able to have it on view all the time to protect it from damage due to light.”

But there are plans to put it back on display as part of a huge exhibition opening in 2018.

In a recent blog post, Eric Jentsch, deputy chair and curator, Division of Culture and the Arts, recalled: “When I was a kid I saw Fonzie’s jacket on display here at the museum. Not only was I excited that something I was so interested was on display, but also that I was shocked at how different from how it was than the image in my mind. For example, it was brown, (while I thought they were always black), and it was much smaller than I would have thought (no offense, Mr. Winkler). It sounds goofy but it really made me examine the things I thought were ‘cool’ more critically. Now that’s basically my job!”

Henry Winkler in 2008 with his “Happy Days” leather jacket and Smithsonian entertainment curator Dwight Blocker Bowers Courtesy of the Smithsonian

“Happy Days” ran for for 255 episodes over 10 years, and Winkler was 28 — already way past his teenage years — when the series debuted in January 1974.

While ABC may have forced Fonzie into extending his adolescence (or perhaps just his adolescent behavior) a bit excessively, Winkler has aged gracefully into other TV roles, as on USA Network’s “Royal Pains,” where he played the somewhat shady dad to concierge doctor Hank Lawson (Mark Feuerstein) and his brother (Paulo Costanzo). He’s also recently recurred on “Parks and Recreation” as Dr. Saperstein and on Adult Swim’s “Childrens Hospital” as Sy Mittleman.

Winkler spends his off-screen time raising awareness about dyslexia — a learning disability with which he struggled when he was growing up. Though he barely made it through high school, he went on to attend Boston’s Emerson College, but didn’t learn that he had dyslexia until years later, when he was 31. According to a February 2015 article in the Atlantic, Winkler simply thought he was stupid until he was diagnosed with dyslexia — believed to affect as many as one in five students. The confident and commanding Fonzie, the Atlantic declared, “was a facade for a man who’d spent his entire life assuming his intelligence just wasn’t, as he put it, ‘up to snuff.'”

The BBC’s “Hank Zipzer,” on which he’s a series regular, playing Mr. Rock, is actually based on a book series penned by Winkler and co-author Lin Oliver about a boy with dyslexia. (Winkler and Oliver have written more than two dozen books together.)

So happy 70th birthday, Mr. Winkler — our beloved Fonzie, who went on to prove he was so much more than just Fonzie.